I must say I am still perplexed by this "if
they are unable to provide financing" mentality.
YOU are responsible for your creditworthiness- not the dealership. Whether or not YOU can get financing has NOTHING to do with what the dealer is
ABLE to do. Now- IF the dealer has pre-approved you and THEN they can't provide financing, you might have a case- given you haven't done something to damage your credit from the time you are pre-approved and taking delivery.